In certain sectors of the workforce, employees are often required to wear clothing having a high visibility, to increase the awareness of persons around them to their presence. Examples of such sectors include areas exposed to a relatively high degree of hazardous vehicular traffic, e.g. road construction or maintenance, police officials, emergency personnel.
This is normally accomplished through the use of high-visibility (“Hi-Vis”) jackets, having a mixture of retroreflective tape areas (these being the highest reflectivity material shaving the ability to return a substantial portion of incident light in the direction of origination of the light, used in reflective armbands and the like), high visibility fabric panels (such as fluorescent yellow and orange fabrics used in safety vests) and lower visibility panels which do not contribute to the calculated reflectivity under the regulatory standards.
Various standards exist in order to classify the effectiveness of such high visibility clothing. In Europe, the EN 471 standard dictates the various levels of classification for personal protective equipment (PPE) clothing, while the publication ANSI/ISEA 107 entitled “American National Standard for High-Visibility Safety Apparel” provides similar levels of classification in the USA. EN 471 sets the minimum area of retroreflective material and background fluorescent material (e.g. high visibility orange or yellow) required for each classification, from class 1 (most lenient) to class 3 (most stringent, and therefore highest visibility level). Table 1 below lists the requirements for the different EN 471 classes.
TABLE 1EN 471 Classification, expressed in cm squaredMinimum backgroundMinimum retroreflectiveEN 471 Classfluorescent material (cm2)material/tape (cm2)Class 114001000Class 250001300Class 380002000
The use of PPE classification systems such as EN 471 and ANSI/ISEA 107-1999 provides for agreed standards that can be employed to meet health and safety requirements in various industries. Traditionally, suppliers provide ready-made garments derived from a design that has been determined to fit into one of the prescribed classifications. However, such classifications are rigorously determined, and any subsequent addition of logos or crests result in an alteration of the design, as some of the retroreflective material of the garment may be obscured by the addition. Correspondingly, the previously-prescribed classification may no longer be valid.
In recent times, there has been increased use of mass customisation techniques, particularly in the field of garment design. Mass customisation allows for a user to employ a computer-based system to take a basic template design and create custom garments, e.g. sportswear having company-specific branding and colour scheme. Through the use of a software program, e.g. a Java applet on a website, a user can alter each of the features of their design until they produce a garment design that is acceptable to the user's requirements. However, the importance of classification systems for PPE garments results in a degree of inflexibility when such garment design is implemented in known mass customisation systems.
As is well known in the art, the conventional process of providing a certified garment begins with a designer creating a design for a garment. The shape of the garment is created by designing a number of flat panels, often with curved edges such that, when sewn together during garment assembly, a 3-dimensional shape is created by virtue of the shapes and sizes of the individual flat fabric panels making up the garment.
The design process, therefore, requires firstly, that a pattern is created, specifying the shape of each piece for a given garment size. Since a high visibility garment usually involves a number of different fabrics (colours, materials, reflectivity levels), the pieces are grouped by fabric, so that all pieces using the same material and colour are grouped together. Each group of pieces is then arranged in what is known as a “cut-make-trim” or CMT arrangement, i.e. a layout allowing the fabric pieces to be cut from a length of fabric with maximum efficiency, taking account of tolerances, the direction of weave or pattern (if any) for each piece, and so on.
When the CMT pattern has been specified for each fabric used in the design, a calculation is performed to determine, for each fabric, the overall area of that fabric used in the CMT layout, less tolerances and any assigned logo area. The design is locked at this point and the CMT and accompanying calculations are then sent to a certification body which certifies the CMT design.
Once the CMT design is certified it cannot be changed. A company offering “customised” apparel to customers will in reality offer a range of approved designs, each having its own certification (achieved in the manner outlined above) and will allow customisation by application of a logo in the place provided by a place holder Such services do not enable a customer to change the colour of various panels as this would invalidate the certification and require a new CMT to be prepared, based on the new mix of fabrics, and for this CMT design to be sent for independent certification.
A problem associated with this system however is the fact that each different design must be independently certified. Should a user want a design which is different to one of the pre-certified templates, then this will be a new design not benefiting from the certification of earlier designs, and therefore the user will not know for certain what the final classification of their design will be until after the design has been finalised and submitted for certification.
This system impedes the process of iterative design of the safety garment, as a number of different designs may have to be made into finalised prototypes which then undergo the standard certification procedure. This results in considerable delays (from a couple of weeks to several months) between iterations, and can be extremely frustrating if a single piece of the design has to be altered, which results in the new design requiring a completely new certification. Such an exercise is not suitable for providing an automated design system with acceptably quick turnaround of the user's design ideas.